6: QRS Axis and Voltage

Question 1

What angles comprise right axis deviation?

Answer 1

+90 to +180 degrees

Question 2

The mean direction of electrical forces in the frontal plane.

Answer 2

Axis

Question 3

What angles comprise left axis deviation?

Answer 3

-30 to -90 degrees

Question 4

Anything not caught in the degrees of deviation for right and left axis deviations.

Answer 4

Indeterminate Axis

Question 5

What angles comprise normal axis?

Answer 5

0 to +90 degrees (possibly as far back as -30)

Question 6

In the normal axis, are Leads 1 and aVF heading in a general positive or negative direction?

Answer 6

Lead 1: Positive

Lead aVF: Positive

Question 7

In the right axis deviation, are Leads 1 and aVF heading in a general positive or negative direction?

Answer 7

Lead 1: Negative

Lead aVF: Positive

Question 8

In the left axis deviation, are Leads 1 and aVF heading in a general positive or negative direction?

Answer 8

Lead 1: Positive

Lead aVF: Negative

Question 9

In the indeterminate axis, are Leads 1 and aVF heading in a general positive or negative direction?

Answer 9

Lead 1: Negative

Lead aVF: Negative

Question 10

Which 2 conditions may be associated with ST-T abnormalities (ST Segment strain patterns)?

Answer 10

Left Ventricular Hypertrophy (QRS Abnormality Only)

Right Ventricular Hypertrophy

Question 11

T/F Early repolarization is abnormal.

Answer 11

False. It can be a normal variant in some healthy adults.

Question 12

T/F Juvenile T Waves can be a normal variant in young adults.

Answer 12

True